Packaging machine and method and article produced thereby

ABSTRACT

A machine for packaging a workpiece in a heat-sealable film, including a U-shaped sealing pad and heater, means for establishing a longitudinal reach of film adjacent to the sealing pad, the sealing pad and the heater being movable between a receiving position and a sealing-severing position, means for urging the workpiece against the reach of film when the heater and the sealing pad are in the receiving position to provide superimposed lengths of film positioned between the sealing pad the the heater and forming an envelope open along one side and the ends of the workpiece, the heater in the sealing-severing position overlying the sealing pad and being in contact with the superimposed lengths of film to seal and sever the same along the one side and the ends of the workpiece. A method for packaging the workpiece in the heat-sealable film is disclosed as is the article of manufacture produced thereby.

Bahnsen States Patent [54] PACKAGING MAEHINE AND METHUID AND ARTICLEPRODUCED THEREBY [72] Inventor: Erwin B. Bahnsen, l-linsdale, 111.

[73] Assignee: Steiner American (Corporation, Salt Lake City, Utah 221Filed: May28, 1969 211 Appl.No.: 828,533

[ heh. 23, 11973 including a U-shaped sealing pad and heater, means for,

establishing a longtudinal reach of film adjacent to the sealing pad,the sealing pad and the heater being movable between a receivingposition and a sealing-severing position, means for urging the workpieceagainst the reach offilm when the heater and the sealing pad are in thereceiving position to provide superimposed lengths of film positionedbetween the sealing pad the the heater and forming an envelope openalong one side and the ends of the workpiece, the heater in thesealing-severing position overlying the sealing pad and being in contactwith the superimposed lengths of film to seal and sever the same alongthe one side and the ends of the workpiece. A method for packaging theworkpiece in the heat-scalable film is disclosed as is the article ofmanufacture produced thereby.

26 Claims, 20 Drawing Figures WWW I H 2 E? W? INVENTOR ERW/N a. BAHNSENATTYS.

EL WJQY MHEUFEB 2 2 1912 SHEET UMUF H SHEET USUF 11 SHEET BB BF "H13,6&3,397

SHEET UBUF H PATENIEnFB22 I972 3,643,397

SHEET 11 0F 11 PACKAGING MACHINE AND METHOD AND ARTICLE PRODUCED THEREBYThe present invention relates to a machine and method for packaging aworkpiece in a heat-sealable film to produce a package of the workpiecein a closed envelope of the heatsealable film.

lt is an important object of the present invention to provide a machinefor packaging a workpiece in a heat-scalable film comprising a frame, agenerally U-shaped sealing pad mounted on the frame and defining withinthe sealing pad a work area, means for establishing a longitudinal reachof film normally disposed adjacent to the sealing pad, a generally U-shaped heater mounted on the frame and shaped and arranged to overliethe sealing pad, means for urging a workpiece against the reach of filmand into the work area to provide superimposed lengths of filmpositioned between the sealing pad and the heater and forming anenvelope open along one side and the ends of the workpiece, drivemechanism providing relative movement of the heater and the sealing padbetween a receiving position and a sealing-severing position, thesealing pad and the heater in the receiving position being spaced apartto receive a workpiece in the work area, the sealing pad and the heaterin the sealing-severing position being juxtaposed to place the heater incontact with the superimposed lengths of film to seal and sever the samealong the one side and the ends of the workpiece, thus to provide apackage of a workpiece in a closed envelope of the heat-sealable filmand to reestablish a longitudinal reach of film adjacent to the sealingpad.

Another object of the present invention is to provide a machine of thetype set forth in which the generally U-shaped sealing pad is fixedlymounted on the frame and the generally U-shaped heater is shiftablymounted on the frame and movable between a receiving position in whichthe heater is spaced from the sealing pad to receive a workpiece in thework area and a sealing-severing position in which the heater isjuxtaposed with the sealing pad to place the heater in contact with thesuperimposed lengths of film to seal and sever the same along the oneside and the ends of the workpiece.

A further object of the present invention is to provide a machine of thetype set forth in which the generally U-shaped sealing pad mounted onthe frame is shaped to provide a central U-shaped trough therein suchthat when the heater and the sealing pad are in the sealing-severingposition thereof, they are juxtaposed to place the heater in the troughand in contact with the superimposed lengths of film to seal and severthe same along the one side and the ends of the workpiece.

Another object of the present invention is to provide a machine of thetype set forth in which a film guide is mounted on the frame adjacent tothe heater and positioned normally to hold the film adjacent to but outof contact with the heater, the guide being movable between a receivingposition and a sealing-severing position, the guide and the sealing padcooperating in the sealing-severing positions thereof to providesuperimposed lengths of film positioned between the heater and thesealing pad and forming an envelope open along one side and the ends ofthe workpiece.

A still further object of the present invention is to provide a machineof the type set forth in which the generally U-shaped sealing padincludes two spaced-apart generally parallel legs and a bightinterconnecting the legs and extending therebeyond, the bight and thelegs defining a work area therebetween, and in which the generallyU-shaped heater includes two spaced-apart generally parallel legs and abight interconnecting the legs and extending therebeyond, the legs andthe bight of the heater being shaped and arranged to overlie the padlegs and the pad bight respectively, the reach of film normally disposedadjacent to the sealing pad having a width no greater than the length ofthe bight with a seam extending transversely of the longitudinal reachof film.

Another object of the present invention is to provide a machine of thetype set forth in which a supply mechanism is mounted on the frame forrotatably supporting a roll of heatsealable film to provide thelongitudinal reach of film normally disposed adjacent to the sealingpad.

Another object of the present invention is to provide a machine of thetype set forth in which tilm from the roll of film rotatably supportedby the supply mechanism is withdrawn from the roll by movement of theheater and the sealing pad toward one another to supply film to thelongitudinal reach of film and to the envelope.

A further object of the invention is to provide a machine of the typeset forth in which a tension mechanism is mounted in the frame formaintaining the reach of film taut and to maintain the superimposedlengths of film positioned between the sealing pad and the heater taut.

A still further object of the present invention is to provide a machineof the type set forth in which a first film supply mechanism is mountedon the frame for rotatably supporting a first roll of heat-sealable filmand a second film supply mechanism is mounted on the frame spaced apartfrom the first supply mechanism for rotatably supporting second roll ofheat-scalable film to provide a longitudinal reach of film normallydisposed adjacent to the sealing pad, the first and second rolls of filmbeing joined at a seam extending transversely from the reach of filmadjacent to the sealing pad and the film forming the envelope beingwithdrawn from the rolls of film on the first and second supplymechanisms.

Another object of the present invention is to provide a machine of thetype set forth in which the film for forming the envelope is withdrawnfrom the first roll of film during movement of the heater and thesealing pad to the sealing-severing position and film is withdrawn fromthe second roll to supply a small amount of the film to the reach offilm when the heater and the sealing pad are in the sealing-severingposition for indexing the same with respect to the sealing pad.

Another object of the preset invention is to provide a machine of thetype set forth in which a feed platfonn is mounted on the frame and isshiftable between a workpiecereceiving position and a workpiece-deliveryposition, the feed platform in the workpiece-delivery position urgingthe workpiece against the reach of film and into the work area toprovide superimposed lengths of film for forming the envelope open alongone side and the ends of the workpiece and the feed platform in theworkpiece-receiving position being disposed adjacent to the sealing padin position to receive a workpiece thereon.

A still further object of the present invention is to provide a machineof the type set forth in which a chute is positioned below the work areato receive a workpiece thereon and extends to a discharge point.

Another object of the present invention is to provide a machine of thetype set forth in which the workpiece that is packaged in a closedenvelope of the heat-scalable film exits from the machine along thechute to a shrink tank in which the heat-scalable film is heated toatemperature less than the melting point of the heat-scalable film torelieve stress in the film and provide a relatively smooth surface forthe heat-sealable film.

A still further object of the prevent invention is to provide an articleof manufacture including a completely enclosed roll of heat-sealablefilm generally in the same shape as the outer surface of the roll, thefilm having a U-shaped first seam extending at least along one end andthe longitudinal side of the roll, the U-shaped first seam having twoparallel legs and a bight interconnecting the legs and a second seam inthe film adjacent to the first seam and interconnecting the legs of thefirst seam.

A still further object of the present invention is to provide animproved film supply mechanism which ensures proper feeding of the filmfrom rolls thereof throughout the entire diameters of the rolls.

A still further object of the present invention is to provide a methodfor packaging a clean an dry roll of toweling in a heatsealable film inwhich the toweling is urged against a longitu dinal reach of film toprovide an envelope open along one side and the ends of the roll oftoweling and heat-sealing the envelope along the open sides thereof toprovide package of a roll of clean and dry toweling completely enclosedin an envelope heatlsealable film.

The invention, both as to its organization and method of operation,together with further objects and advantages thereof, will best beunderstood by reference to the following specification and drawingshereof as follows:

FIG. 1 is a side view in elevation of the packaging machine of thepresent invention;

FIG. 2 is a front view in elevation of the packaging machine of FIG. 1;

FIG. 3 is a view in vertical section of the packaging machine takenalong the line 3-3 of FIG. 2;

FIG. 4 is a view in horizontal section of the packaging machine takenalong the line 4-4 of FIG. 3;

FIG. 5 is an enlarged view in section of the sealing pad and heaterwithout the support assembly therefor shown in FIG. 3;

FIG. 6 is a view in section of the heater looking up from the bottomthereof taken along the line 6-6 of FIG. 5;

FIG. 7 is a view in vertical section of the heater and the sealing padshown in FIG. 5;

FIG. 8 is an enlarged view in vertical section of a portion of theheater and the sealing pad shown in FIG. 7;

FIG. 9 is a diagrammatic and schematic view of the control mechanism ofthe packaging machine and certain components thereof;

FIGS. 10 to are sequential diagrammatic views of the operating steps ofthe packaging machine;

FIG. 16 is a plan view of a packaged workpiece as produced by themachine of FIGS. 1 to 15;

FIG. 17 is a view in cross section of the packaged workpiece shown inFIG. 16, taken along line 17--17;

FIG. 18 is a perspective view of the packaged workpiece after shrinkingof the plastic envelope about the workpiece; and

FIGS. 19 and 20 are fragmentary views illustrating an alternative filmsupply mechanism.

Referring now to FIGS. 1 to 4, there is disclosed a packaging systemincluding a packaging machine 101 and a shrink tank 102, the packagingmachine 101 having a frame including air of parallel spaced-apartupstanding panels 111 interconnected by a plurality of tie rods 112 andhaving a feed-platform support 113 mounted on one of the side panels 111.

As shown particularly in FIGS. 2 and 4, an infeed conveyor is providedon the machine 101 to the right in FIG. 2 and includes an endless belt121 supported at either end by rollers 122 which are connected by anidler chain 123 meshing at one end with an idler gear 124 mounted on anidler shaft 125 and meshing at the other end with a gear 126 mounted ona gear shaft 127. Also mounted on the gear shaft 127 on a gear (notshown) is a drive chain 128 which is supported at its other end by drivegear 129 mounted on a drive shaft 130 of motor 131. There is alsoprovided on either side of the infeed conveyor 120 a front retainingwall 132 and a rear retaining wall 133 on either side of the endlessbelt 121 and spaced apart a distance greater than the width of aworkpiece 135 which rides on the endless belt 121 in a direction shownby arrow 136.

The workpiece 135 is transported by the infeed conveyor 120 to thefeed-transport mechanism which includes a feed platform 141 havingbaseplate 142 connected to an outwardly inclined rear support plate 143and an inwardly inclined front support plate 144 which terminates at oneedge in an inwardly turned flange 145 that holds pin 146. There is alsoconnected to baseplate 142 a downwardly depending flange 147 having aelongated slot 148 therein.

Cooperating with the feed platform 141 and, more particularly elongatedslot 148 in the downwardly depending flange 147, is an L-shaped feedactuator arm 150 pivotally mounted on side panel 111 with shaft 151 andhaving a cam follower 152 at the long end of the L and a bolt 153disposed in elongated slot 148 and nut 154 connected to the bolt 153 tomaintain the connection between the feed actuator arm 150 and the feedplatform 141. The workpiece 135 will be moved in the direction shown byarrow 156 upon movement of the feed platform 141 in response to movementof the feed actuator arm 150. Movement of the workpiece 135 off the feedplatform 141 is prevented by an upstanding plate 157 pivotally connectedto a hinge 158 and by the outwardly inclined rear support plate 143.

A film supply mechanism 160 of the packaging machine 101 includes anupper film supply 161 containing an upper film roll 162 and an upperfilm supply drive roll 163 which has an upper drive shaft 164 joumaledin a pair of upper drive shaft flange bearings 165 connected to the sidepanels 111 by a plurality of bolts 166. A pair of upper guide flanges167, mounted on shaft 164, are spaced apart a distance greater than thelength of roll 162 to prevent movement of the upper film roll 162longitudinally of the upper film drive roll 163. A plurality of knurledrubber heels 168, fixedly mounted on the upper drive shaft 164,provide'for nonslip rotation of the upper film roll 162 with rotation ofthe rubber wheels 168. There is also provided in the upper film supply161 an upper supply idler roll 173 located rearward of the upper filmdrive roll 163 and including an upper idler shaft 174 joumaled to theupstanding side panels 111 as hereinbefore described with respect to theupper film drive roll 163. The upper idler shaft 174 has fixedly mountedthereon a plurality of spaced-apart knurled rubber wheels 178. The upperidler shaft 174 may also have mounted thereon a plurality of flanges inaddition to or in lieu of the flanges 167 on the drive shaft 164. Theshaft 164 is connected to an upper drive motor 177 mounted on frame 1 10by motor mounting plate 179.

The film supply mechanism 160 also includes a lower film supply 81having a lower film roll 182 and a lower film dn've roll 183. The lowerfilm drive roll 183 includes a lower drive shaft 184 having mountedthereon a pair of lower guide flanges 187 spaced apart a distancegreater than the length of the lower film roll 182 to prevent movementof the roll 182 longitudinally along the lower film drive roll 183. Alsodisposed on the lower film drive shaft 184 are a plurality ofspaced-apart knurled rubber wheels 188. The lower film supply 181 alsoincludes a lower film idler roll 193 having a lower idler shaft 194joumaled in a pair of lower idler shaft flange bearings 195 mounted onthe side panels 111 by a plurality of bolts 196. The lower drive shaft184 is driven by a lower drive motor 197 mounted on the frame 110 by amotor mounting plate 199 and slippage of the lower film roll 182 isprevented by a plurality of spaced-apart knurled rubber wheels 198mounted on the lower idler shaft 194. The lower idler shaft 194 may havemounted thereon a plurality of flanges in addition to or in lieu of theflanges 187 mounted on the drive shaft 184.

As clearly seen in the drawings, a reach of film 200 is establishedbetween the upper film roll 162 and the lower film roll 182 and iscomprised of an upper portion 201 from the upper film roll 162 and alower portion 202 from the lower film roll 182 meeting at a seam 204which extends transversely of the longitudinal reach of film 200. Aswill be later explained, film from the upper film roll 162 and the lowerfilm roll 182 is fed by the upper film drive roll 163 and the lower filmdrive roll 183 to form a loose envelope 205 around the workpiece 135 andto provide lengths of film 206 connecting the envelope 205 and the reachof film 200. During the sealing and severing of the lengths of film 206,a seam 207 is formed to close the envelope 205 and new seam 204 isformed to reestablish the reach 200.

The longitudinal reach of film 200 is maintained taut by tensioningmechanism 210 including a U-shaped bracket 211 having parallelspaced-apart legs 212 and a bight 213 interconnecting the legs 212.Parallel to the bight 213 and spaced therefrom is a weight 214interconnecting the legs 212 and extending therebeyond. The U-shapedbracket 211 is mounted on the frame 110 by a pair of triangularly shapedsleeve supports 215 pivotally mounted to the upstanding side panels 111by pins 216. As seen in FIG. 3, the upper portion 201 of the reach offilm 200 is fed from the bottom of the upper film roll 162 over thebight 213 of the U-shaped bracket 211 and then downwardly to meet thelower portion 232 at the seam 234 of the reach of film 233.

The seam 234 is normally disposed adjacent to a sealing and severingmechanism 223 which includes a jaw frame 225 formed in part of aU-shaped sealing pad 233. The pad 233 includes a pair of parallelspaced-apart legs 231 interconnected by a bight 232 having outwardlyextending portions 233. As seen more particularly in FIGS. 7 and 3, theU-shaped sealing pad 230 includes a U-shaped base plate 234 havingmounted thereon a pair of spaced-apart yieldable pads 235 havingdownwardly and outwardly sloping top surfaces 236 and on the interiorfaces 237 of yieldable pads 235 there are provided offset surfaces 233.

Between the yieldable pads 235 is positioned a U-shaped cooling tube 243supported by offset surfaces 233 of pads 235 and mounted on the U-shapedbase plate 234 by a plurality of support poles 241 and fixed thereby bya plurality of nuts 242. As seen most clearly in FIG. 4, a pair ofcooling supply pipes 243 and'pair of cooling exit pipes 244 provide acooling flow path through the cooling tube 243 as shown by thedirectional arrows 245 and 246 for the coolant 247 to flow. The interiorfaces 237 of the yieldable pads 235 and the cooling tube 243 definetrough 249.

The flange 225 further includes a U-shaped heater 253 having a pair ofparallel spaced-apart legs 251 interconnected by a bight 252 havingportions 253 extending outwardly of the legs 251. As is most clearlyseen in F168. 5-7, U-shaped heater 250 is formed of a U-shaped cap 254having mounted thereon and depending therefrom a heat-transfer base 255by bolts 256, the heat-transfer base 255 having therein at the topthereof a triangular groove 257. The heat-transfer base 255 includes apair of parallel straight wall portions 253 and a pair of inwardlyinclined wall portions 259 meeting and terminating in a generallyV-shaped knife edge 263. At one end of the legs 251 there are providedinwardly inclined surfaces 259a and 25% to assure that the knife edges263 on the legs 251 meet the knife edge 263 on the bight 252. Positionedin the triangular groove 257 in the heat-transfer base 255 is a heatingelement 265 and also located in the heat-transfer base 255 and spacedfrom the heating element 265 is a temperature sensor 266. coextensivewith the bight 252 of the U-shaped heater 253 is a weight 267 mounted ontop of the U-shaped cap 254.

There is also provided a pair of U-shaped guides 273 mounted by bolts271 to the U-shaped cap 254 and separated therefrom by heat insulators272. The lowest most portions of guides 273 are inwardly turned to formflanges 275 which hold therein a generally U-shaped cooling tube 233. Asseen in FIG. 6, the cooling tube 233 is continuous and is connected to acoolant supply pipe 233 and a coolant exit pipe 234 to provide a'coolantflow path, as seen by directional arrows 235 and 236, for the coolant287 that is carried within the cooling tube 233, as shown in FIG. 3.

The generally U-shaped heater 253 is mounted on the frame 113 ashereinafter described. A pair of boomerang-shaped arms 293 having anupper portion 291 and a lower portion 292 are fixedly mounted on twoseparately overhung pivot shafts 293 which are joumaled in a pair offlange bearings 294 mounted on the side panels 111. At the ends of thelower portions 292 of the boomerang-shaped arms 293 are provided two camfollowers 295, the purpose of which will be hereinafter explained, andat the ends of the upper portions 291 of the boomerang-shaped arms 293are mounted braces 296 by bolts 297. Onto the braces 296 are mounted theU- shaped heaters 250 by means of a plurality of L-shaped brackets 298mounted on the braces 296 by a plurality of bolts 299 and mounted on theheater 253 by a plurality of bolts 271.

As seen in FIGS. 3 and 4, the U-shaped sealing pad 233 definestherewithin a work area 333 and positioned below the work area 300 andthe sealing pad 233 is chute 305 leading from the packaging machine 131to the shrink tank 132.

Drive mechanism 310 is provided for the feed-transport mechanism 140 andthe sealing and severing mechanism 223 and includes a main camshaft 311journaled at one end, as shown in FIGS. 2 and 4, in a flange bearing 312mounted on one of the upstanding side panels 111. The other end of themain camshaft 311 is journaled in a rigid coupling 313 which isconnected to a drive shaft (not shown) of a right-angle, three-phasegear-head motor 315 mounted on the frame 113 by motor mount 314. Fromthe left-hand side of the main camshaft 311, as shown in F16. 2, thereis provided a feed actuator arm cam 323, mounted on the camshaft 311 bymounting flange 321, in contact with the cam follower 152 on the longerportion of the L-shaped feed actuator arm 153. Spaced from the feedactuator arm cam 323 is cycle shutoff cam 325 mounted on the maincamshaft 311 by mounting flange 326 and, as shown in FIG. 9, the cycleshutoff cam 235 has a small indent 327 in the periphery thereof. A pairof spaced-apart jaw-frame cams 333 are mounted on the main camshaft 311by mounting flanges 331 and contact the cam followers 295 on theboomerang-shaped arms 293. Adjacent to the rigid coupling 313 is a lowerfilm drive earn 335 mounted on the main camshaft 311 by a mountingflange 336, and as shown in FIG. 9, the lower film drive cam 335 has ashort rise portion 337 on the periphery thereof.

The electrical system 343 controlling the movement of the feed-transportmechanism 143, the film-supply mechanism 163 and the sealing andsevering mechanism 223 will now be described. As shown in FIG. 9, athree-contact switch 345 has one set of three terminals 346, 347 and 343connected to a three-line power supply 352 having inputs L-ll, L-2 andL3 and the switch 345 has the other set of three terminals 349, 353 and351 connected to terminals 363, 362 and 364 respectively of motor startrelay 355 by conductors 366, 367 and 363. The motor start relay 355 hasthree normally open contacts 356, 357 and 353 which upon energization ofthe motor start relay 355 are pulled up to make electrical contactbetween the aforementioned terminals 363, 362 and 364 and terminals 361,363 and 365 of the relay 355. The motor start relay 355 also includes acoil 373 having an upper terminal 371 and a lower terminal 372 and acore 359, both of which act in the usual manner.

There is provided on the feed platform 141 adjacent to the upstandingplate 157 a normally open microswitch 375 which is closed by themovement of a workpiece against the upstanding plate 157 pivotallymounted on the hinge 153. The microswitch 375 has terminals 376 and 377,connected as will hereinafter be described.

The right-angle, three-phase, gear-head motor 315 has three field coils333, 331 and 332 interconnected to terminals 333, 334 and 335. The upperdrive motor 177 has terminals 336 and 337 and the lower drive motor 197has terminals 333 and 339. I V

Adjacent to the cycle shutoff cam 325 is a normally open microswitch 393having a pair of terminals 391 and 392. Adjacent to the U-shaped bracket211 of the tensioning mechanism 213 is a normally open microswitch 395having a pair of terminals 396 and 397 for control of the upper drivemotor 177. Adjacent to the lower film drive cam 335 is a normally openmicroswitch 433 having a pair of terminals 431 and 432 for control ofthe lower film drive motor 197.

The circuitry of the aforementioned electrical components will behereinafter described. The terminal 372 of the coil 373 in the motorstart relay 355 is connected to the terminal 351 of the switch 345 by aconductor 435 and the conductor 368. The terminals 371 of the coil 373is connected to the terminal 377 of the microswitch 375 by a conduct-or436 and a conduc' tor 437. The terminal 371 of the coil 373 is connectedto the terminal 392 of the switch 393 by the conductor 437. The ter'minal 391 of the microswitch 390 is connected to the terminal 353 of theswitch 345 by a conductor 433 and the conductor 367. The terminal 376 ofthe microswitch 375 is connected to the terminal 353 of the switch 345by a conductor 439, a conductor 423 and the conductors 433 and 367.

The terminal 334 of the gear-head motor 315 is connected to the terminal361 of the motor start relay 355 by a conduc tor 410, the terminal 383of the motor 315 is connected to the terminal 363 of the relay 355 by aconductor 411 and a conductor 416 and the terminal 385 of the motor 315is connected to the terminal 365 of the relay 355 by a conductor 412 anda conductor 416.

The terminal 363 of the motor start relay 355 is connected to theterminal 386 of the upper drive motor 177 by a conductor 415, theterminal 365 of the motor start relay 355 is connected to the terminal386 of the microswitch 395 by a conductor 416 and the terminal 397 ofmicroswitch 395 is connected to the terminal 387 of the upper drivemotor 177 by a conductor 417.

The terminal 401 of the microswitch 400 is connected to the tenninal 350of the switch 345 by a conductor 420 and the conductors 423 and 408, theterminal 402 of the microswitch 400 is connected to the terminal 389 ofthe lower drive motor 197 by a conductor 421 and the terminal 388 of thelower drive motor 197 is connected to the terminal 351 of the switch 345by a conductor 422.

The operation of the packaging machine 101 will be described withparticular reference to FIGS. 915. FIG. 10 shows the packaging machine101 in its neutral position in which the feedtransport mechanism 140 isin a workpiecereceiving position and the sealing and severing mechanism220 is in a neutral position. During the time that the packaging machine101 is in its neutral position the coolant 247 is supplied to thecoolant tube 240, the coolant 287 is supplied to the coolant tube 280and the heating element 265 is activated to provide heat to theheat-transfer base 255 and hence to the knife edge 260. The tensioningmechanism 210 is in its filmstorage position maintaining the reach offilm 200 taut; therefore, the microswitch 395 controlling the upperdrive motor 177 is open.

The three-contact switch 345 is then closed to electrically connect thepower supply 352 with the terminal 376 of the normally open microswitch375 as hereinbefore explained, and the other terminal 377 of thenormally open microswitch 375 is electrically connected to the tenninal371 of the coil 370 in the motor start relay 355. As seen from FIG. 9,until the normally open microswitch 375 is closed, the packaging machine101 is not activated regardless of the closing of the three-contactswitch 345.

A workpiece 135 is fed onto the feed platform 141 by means of the infeedconveyor 120 to contact the upstanding plate 157 pivotally mounted onhinge 158 to move the plate 157 and close the normally open microswitch375. The closing of the microswitch 375 energizes the motor start relay355 and pulls up the contacts 356, 357 and 358 thereof and energizes thefield coils 380, 381 and 382 of the gear-head motor 315 which providesclockwise rotation of the main gearshaft 311 and clockwise rotation ofthe cams 320, 325, 330 and 335.

As seen in FIG. 11, as the main camshaft 311 rotates, the feed actuatorarm cam 320 and the jaw-frame cams 330 rotate therewith to providemovement of the feed platform 141 to its workpiece-delivery position andthe sealing and severing mechanism 220 to a receiving position in whichthe U-shaped heater 250 is spaced from the U-shaped sealing pad 230 toreceive the workpiece 135 in the work area 300 and onto the chute 305.The feed platform 141 in its workpiece-delivery position urges theworkpiece against the taut reach of film 200 to initiate the formationof the envelope 205. The urging of the workpiece 135 against the tautreach of film 200 by the feed platform 141 results in movement of thetensioning mechanism 210 from its film-storage position to itsfilm-feeding position in which the normally open microswitch 395 isclosed by movement of the U-shaped bracket 211 to activate the upperdrive motor 177 and to cause rotation of the upper film roll 162, asshown by directional arrow 610, to feed film therefrom to the reach offilm 200 to provide film for the formation of the envelope 205.

Rotation of the main camshaft 311 also results in the closing of thenormally open microswitch 290 due to the rotation of the cycle shutoffcam 325. Since the cycle shutoff cam 325 has a small indent 327 in theperiphery thereof, a slight rotation of the main camshaft 311 results inthe closing of the normally open microswitch 390. When the normally openmicroswitch 390 is closed, a holding circuit for the motor start relay355 is activated to maintain the relay 355 in its closed position duringthe cycle of the packaging machine 101. When the workpiece leaves thefeed platform 141, the normally open microswitch 375 returns to its openposition and but for the cycle shutoff cam 325, the gear-head motor 315would shut off. As best seen in FIG. 9, the cycle shutoff cam 325maintains the motor start relay 355 in its closed condition for amajority of the rotation of the main gearshaft 311. When the tensioningmechanism 210 assumes its film-feeding position, film from the upperfilm roll 162 is positively fed therefrom.

The microswitch 395 is normally open due to the biasing of g thetensioning mechanisms 210 by weight 214 but is closed when the workpiece135 is urged against the reach of film 200.

Reference to FIGS. 12 and 13 shows that film from the upper film roll162 is withdrawn from the roll 162 during the formation of the envelope205 which is open along the length an both ends of the workpiece 135 andthe withdrawal of film from the upper film roll 162 also provides thesuperimposed lengths of film 206 positioned over the yieldable pads 235of the U-shaped sealing pad 230. During the time that the feed platform141 is shifted to its workpiece-delivery position and shifted therefromand during the time the the U-shaped heater 250 is shifted from thereceiving position to the sealing-severing position, as shown in FIG.14, the electrical connections remain the same as hereinabove describedwith reference to FIG. 11.

As seen in FIG. 14, when the U-shaped heater 250 has shifted to thesealing-severing position, the tensioning mechanism 210 has returned toits film-storage position thereby opening the microswitch 395 whichstops the upper film drive motor 177 and halts the rotation of the upperfilm roll 162 and the feeding of film therefrom. The normally openmicroswitch 400 is closed by rotation of the lower film drive cam 335which activates lower drive motor 197 and results in rotation of thelower film roll 182 to supply a small amount of film to the reach offilm 200 and indexes the seam 204 for a purpose hereinafter to beexplained.

As best seen in FIGS. 7 and 8, the U-shaped sealing pad 230 and theU-shaped heater 250 in their sealing-severing position are arranged sothat the inwardly turned flanges 275 of guides 270 hold the reaches offilm 206 tautly against the top surfaces 236 of the yieldable pads 235to maintain the lengths of film 206 taut during the sealing-severingthereof. The inwardly turned flanges 275 also hold down the reaches offilm 206 for a short time after the sealing-severing thereof to allowthe justformed seams 204 and 207 to cool before tension is applied tothem.

The yieldable pads 235 are in thermal contact with the coolant tube 280and are cooled thereby. The cooperation of the coolant tubes 240 and 280cools the lengths of film 206 adjacent thereto so as to prevent themelting thereof during the sealing-severing of the lengths of film 206.In the sealingsevering position, the knife edge 260 is in the trough 249and contacts the superimposed lengths of film 206 and seals and seversthe same along the three open sides of the envelope 205 to form apackage 203 of the workpiece 135 in a closed loose envelope 205 of theheat-sealable film. As seen, the old seam 204 has been moved away fromthe knife edge 260 due to the indexing of the lower film roll 182 duringa prior sealing-severing operation and an envelope seam 207 and a newseam 204 are formed in the lengths of film 206 during thesealing-severing thereof; the seam 207 closes the envelope 205 while thenew seam 204 reestablishes the longitudinal reach of film 200.

As best seen in FIGS. 9 and 14, the lower drive motor 197 is actuated bythe closing of microswitch 400 when the short rise 337 of the lower filmdrive cam 335 closes the switch 400 and completes the circuit betweenthe terminals 388 and 389 of the lower film drive motor 197 and thepower supply 352. Since the short rise 337 is very small, themicroswitch 400 is closed during only a few degrees of rotation of thecamshaft Ell and only about ll inch of film is withdrawn from the lowerfilm roll T52 and provided to the lower portion 252 to the reach of film200. The indexing of the lower film roll T52 moves the seam 2M out ofposition to be contacted by the knife edge 25h and prevents the sealingand resealing of successive envelopes along the same seam. The shortrise 537 of the lower film drive cam 335 and the small indent 327 of thecycle shutoff cam 325 are positioned to prevent operation of the lowerdrive motor 197 when the switch M5 is closed but the motor start relay355 is open.

During the time that the U-shaped heater 25b and the U- shaped sealingpad 235 are in the sealing-severing position, the feed platform Mi hasshifted to its workpiece-receiving position to receive a workpiece 135from the infeed conveyor 1120.

As best seen in H65. 9 to T5, after the sealing of the envelope 205, apackage 2i)? of a workpiece 1135 enclosed in a heat-scalable film exitsfrom the packaging machine Mill along the chute 305 to a discharge pointand into shrink tank Th2 shown in FIG. l. The packaging machine iltlllhas returned to the neutral position shown also in PllG. ill), in whichthe longitudinal reach of film 2tltl is reestablished disposed adjacentto the U-shaped sealing pad 235! and tautly maintained by the tensioningmechanism 21th. if a workpiece T35 is not in position on the feedplatform illll to contact the upstanding plate T57 and thereby close themicroswitch 375, the motor start relay 355 will open upon rotation ofthe cycle shutoff cam 3325 to a position in which the small indent 227on the periphery thereof allows the normally open microswitch 3% to openand deenergize the motor start relay 355. if a new workpiece 135 is inposition on the feed platform Mil to close the microswitch 575, then themotor start relay 355 remains energized and the geanhead motor 3115continues to operate and rotate the main camshift Eli to provide anothercycle of the packaging machine ltli all as hereinbefore explained.

The package 203 is best illustrated in P168. in to 115 and includes aworkpiece 135 enclosed in a loose envelope 2% sealed by a U shaped seam207. The U-shaped seam 207 includes a pair of parallel spaced-apart legportions 2% and a bight portion interconnecting the leg portions 255.There also are illustrated waste film portions 2211 at either end of thepackage 24173, which portions 223 may be severed and discarded or lefton to provide for easier opening of the package 203; a pair of tucks 222occur where any excess film is gathered. Referring to H6. T7, theposition of the new seam 2fi7 is spaced from the preceding seam 254, aspreviously explained with reference to lFlGS. d and M, such spacingbeing provided by the indexing of the lower film roll i152.

After the package 2% exits from the packaging machine iltlll along thechute 355, the waste film portions 2211 may or may not be trimmed anddischarged prior to entry of the package 203 into the shrink tank M2.The shrink tank 102 is simply a container or oven maintained at atemperature between the flow point and the melting point of the film inorder to relieve stresses incurred in the packaging of the workpiece 135and to shrink the loose envelope 265 of film to form a package 503consisting of the workpiece 135 in a closed envelope 505 tightly wrappedaround the workpiece T35 and having in the envelope 5&5 a U-shaped firstseam 5M7 including two spaced-apart leg portions 5% extending along theends of the workpiece T35 and a bight portion interconnecting the legportions 5% and extending along the longitudinal side of the workpieceM5. The envelope 555 also has a second seam 5M adjacent to and generallyparallel to the bight portion of the first seam 507 and interconnectingthe leg portions 555 of the first seam 5m with portions 510 of thesecond seam 5%. It will be appreciated that the seams W T-511d, 557 and555 are derived respectively from the seams 2M, 2M and 2w by shrinkagethereof.

in a constructional example, the packaging machine Mill is about 62inches high and the side panels llllll are flame cut from %-inch thicksteel plates. The workpiece 1135 is a roll of Till clean and drytoweling and the heat-sealable film is a polyethylene resin. The coolanttubes 2d!) and 255 are copper and the coolant is water. in thesealing-severing position, the bottom edges of flanges 275 areone-sixteenth of an inch below the knife edge 251i. The weight 257 issteel while the cap 255 and the heat-transfer base 255 are aluminum andthe yieldable pads 255 are sponge rubber.

The jaw-frame cams 355 are designed so that about of the rotationrepresents the low dwell during which the sealingsevering takes placeand approximately 60 represents the cam rise. About of the high dwellkeeps the jaw frame 225 open to allow film from the upper film roll N52to be withdrawn and form the envelope 255. Since the jaw frame 225 israised upward by the cams 355 and drops by gravity, there is an inherentsafety feature as any object inadvertently placed between the U-shapedsealing pad 2% and the heater 25h will automatically maintain the jawframe 225 in an open position without interfering with the rotation ofthe main cam shaft 311.

The heating element 265 is maintained at 725 F. to prevent contaminationof the heat-transfer base 255 and the shrink tank W2 is maintained at atemperature of about 250 F.

Referring now to FllGS. l5 and 20, there is shown an alternate filmsupply mechanism 765 which includes an upper film roll 1152 supported bya first upper film idler roll 773 which has an upper idler shaft 77ijourna'led to the upstanding side panels llllll as hercinbeforedescribed with respect to the upper film drive roll 1153, the idler roll773 having a pair of spaced-apart guide flanges 777 and a plurality ofknurled rubber wheels 7593 all fixedly mounted on the upper idler shaft774. Spaced apart from the first upper idler roll "773i is a secondupper idler roll 7 M) which includes a pair of freeswinging bearingflanges 74M having holes 742 in the freeswinging ends, the flanges Willbeing mounted to the upstanding side panels illll by fixtures 745. Thesecond upper idler roll 7410 also including an idler shaft 75d supportedby the flanges Will and carrying thereon a plurality of spaced-apartknurled rubber wheels 745. As seen, the second idler roll 74d is thusswingedly mounted on the frame illlll for rotation about an axisshiftable in the direction of arrows 749. There is also provided anupper film drive roll 7463 including an upper film drive shaft 7Mjournaled to the upstanding side panels llll as hereinbefore describedwith respect to the upper film drive roll T63, the drive shaft 764!carrying a plurality of spacedapart knurled rubber wheels 768 thereon.

The upper portion 2M of the reach of film 20% is withdrawn from theupper film roll 1162 as shown and passes over the second idler roll 7 thand under the drive roll 753 and then upward over a bight 5113 between apair of arms hill of a generally U-shaped tensioning mechanism filth. Asthe film is withdrawn from the film roll 1152, as hereinbeforedescribed, the film roll 162 rotates in the direction shown by an arrow7 26, the first and second idler rolls 773 and 74351, respectively, andthe drive roll 753 all rotate in the directions shown by the arrowsthereon, the second idler roll 7 th being free to swing in a directionshown by the arrows 7 th and the film travels up to and over thetensioning mechanism 51th as shown by two arrows 74 7 and 755.

The film supply mechanism 76% also includes a lower film roll i182supported by a first lower film idler roll 7935 which includes a firstlower idler shaft 7% journaled to the upstanding side panels lllll ashereinbefore described with respect to the upper film drive roll 11533,the shaft 794 carrying thereon a pair of spaced'apart guide flanges 797and a plurality of knurled rubber wheels 7%. A second lower film idlerroll 75ft includes a free-swinging pair of flanges 751 each having ahole 752 in the free-swinging end, and the flanges 7511 being mounted onthe upstanding side panels llllll by a fixture 753. The second loweridler roll 750 also includes an idler shaft 75d supported by the flanges75ll and carrying thereon a plurality of spaced apart knurled rubberwheels 755. As seen, the second idler roll 750 is thus swingedly mountedon the upstanding side panels Hill for rotation about an axis shiftablein the direction of arrows 759. There is also provided a lower filmdrive roll 783 including a lower film drive shaft 784 mounted on theupstanding side panels 111 as hereinbefore described with respect to theupper film drive roll 163, the drive shaft 784 carrying thereon aplurality of spaced-apart knurled rubber wheels 788.

The lower portion 202 of the reach of film 200 is withdrawn from theroll 182 during rotation thereof in the direction of an arrow 756, thefilm passing over the second idler roll 750, underneath the drive roll783 and upwards to form a part of the longitudinal reach of film 200,the idler rolls 793 and 750 and the drive roll 783 all rotating in thedirection of the arrows shown thereon and the lower portion of the film202 moving in the direction of an arrow 757.

The alternate embodiment of the film supply mechanism described aboveprevents clinging of the film to the film roll when the tension of thefilm on the roll would normally tend to make the film cling and wraparound the roll rather than being withdrawn therefrom. The weight of thefilm roll on the two idler rolls produces a force which forces thesecond, freely swingable idler roll against the drive roll and preventsslippage of the film. As the film roll diameter decreases, the perimeterwill fall deeper between the two idler rolls and the force of the secondidler roll against the drive roll would increase but the weight of thefilm roll decreases and the force of the second idler roll against thedrive roll remains about the same. The distance between the two idlerrolls is less than the diameter of the core of the film roll to preventthe core of the film roll from falling between the idler rolls when allthe film has been used.

In view of the foregoing, it is apparent that there has been provided anarticle of manufacture of a workpiece completely enclosed in aheat-sealable film and apparatus and method for manufacturing thereof.While there has been described what is at present considered to be thepreferred embodiment of the invention, it will be understood thatvarious modifications may be made therein and it is intended to cover inthe appended claims all such modifications as fall within the truespirit and scope of the invention.

Iclaim:

l. A machine for packaging a workpiece in a heat-scalable film, saidmachine comprising a frame, a generally U-shaped sealing pad mounted onsaid frame and shaped to form a film bridge defining a central U-shapedtrough therein and defining within said sealing pad a work area, meansfor establishing a longitudinal reach of film normally disposed adjacentto said sealing pad, a generally U-shaped heater mounted on said frameand shaped and arranged to overlie said sealing pad, means for urging aworkpiece against the reach of film and into said work area to providesuperimposed lengths of film positioned between said sealing pad andsaid heater and forming an envelope open along one side and the ends ofthe workpiece, drive mechanism providing relative movement of saidheater and said sealing pad between a receiving position and asealing-severing position, said sealing pad and said heat in saidreceiving position being spaced apart to receive a workpiece in saidwork area, said sealing pad and said heater in said sealing-severingposition being juxtaposed to place said heater in said trough and incontact with the superimposed lengths of film to seal and sever the samealong one side and the ends of the workpiece, thus to provide a packageof a workpiece in a closed envelope of the heat-scalable film and toreestablish a longitudinal reach of film adjacent to said sealing pad.

2. The machine defined in claim 1, wherein said sealing pad includes apair of spaced-apart generally U-shaped yieldable pads.

. 3. The machine defined in claim 2, wherein said yieldable pads aremade of sponge rubber.

4. The machine defined in claim 1, wherein said sealing pad is fixedlymounted on said frame said heater is shiftably mounted on said frame andmovable between said sealingsevering position and said receivingposition.

5. The machine defined in claim 1, wherein said heater includes agenerally U-shaped knife edge shaped to overlie the trough in saidsealing pad.

6. A machine for packaging a workpiece in a heat-scalable film, saidmachine comprising a frame, a generally U-shaped sealing pad mounted onsaid frame and defining within said sealing pad a work area, a supplymechanism mounted on said frame for rotatably supporting a roll ofheat-sealable film to provide a reach of film normally disposed adjacentto said sealing pad, a generally U-shaped heater mounted on said frameand shaped and arranged to overlie said sealing pad, means for urging aworkpiece against the reach of film and into said work area to providesuperimposed lengths of film positioned between said sealing pad andsaid heater and forming an envelope open along one side and the ends ofthe work-' piece, drive mechanism providing relative movement of saidheater and said sealing pad between a receiving position and asealing-severing position, means for operating said supply mechanism towithdraw film from the roll of heat-scalable film to supply the same tothe reach of film for forming the envelope during movement of saidheater and said sealing pad to said sealing-severing position, saidsealing pad and said heater in said receiving position being spacedapart to receive a workpiece in said work area, said sealing pad andsaid heater in said sealing-severing position being juxtaposed to placesaid heater in contact with the superimposed lengths of film to seal andsever the same on one side and the ends of the workpiece, thus toprovide a package of a workpiece in a closed envelope of a heat-scalablefilm and to reestablish a reach of film adjacent to said sealing pad.

7. The machine set forth in claim 6, wherein said supply mechanismincludes a pair of horizontally disposed spacedapart rolls for holding aroll of heat-scalable film thereon.

8. The machine set forth in claim 6, wherein said supply mechanism ismounted above said sealing pad and said heater to feed the longitudinal.reach of film downwardly adjacent to said sealing pad.

9. The machine set forth in claim 6, and further comprising drivestructure positively to feed film from a roll thereof mounted on saidsupply mechanism.

10. A machine for packaging a workpiece in a heat-scalable film, saidmachine comprising a frame, a generally U-shaped sealing pad mounted onsaid frame and defining within said sealing pad a work area, a supplymechanism mounted on said frame for rotatably supporting a roll ofheat-scalable film to provide a longitudinal reach of film normallydisposed adjacent to said sealing pad, a generally U-shaped heatermounted on said frame and shaped and arranged to overlie said sealingpad, means for urging a workpiece against the reach of film and intosaid work area to provide superimposed lengths of film positionedbetween said pad and said heater and forming an envelope open along oneside and the ends of the workpiece, drive mechanism providing relativemovement of said heater and said sealing pad between a receivingposition and a sealing-severing position, means for anchoring the filmon the side of said work area opposite that on which is disposed saidsupply mechanism, operation of said drive mechanism to move said heaterand said sealing pad toward one another causing film to be fed from aroll thereof mounted on said supply mechanism into the longitudinalreach of film, said sealing pad and said heater in said receivingposition being spaced apart to receive a workpiece in said work area,said sealing pad and said heater in said sealing-severing position beingjuxtaposed to place said heater in contact with the superimposed lengthsof film to seal and sever the same along one side and the ends of theworkpiece, thus to provide a package of a workpiece in a closed envelopeof the heat-sealable film and to reestablish a longitudinal reach offilm adjacent to said sealing pad.

11. A machine for packaging a workpiece in a heat-scalable film, saidmachine comprising a frame, a generally U-shaped sealing pad mounted onsaid frame and defining within said sealing pad a work area, a supplymechanism mounted on said frame for rotatably supporting a roll ofheat-scalable film to provide a longitudinal reach of film normallydisposed adjacent to said sealing pad, a generally U-shaped heatermounted on said frame and shaped and arranged to overlie said sealingpad, tensioning mechanism mounted on said frame for maintaining thereach of film taut, means for urging a workpiece against the taut reachof film and into said work area to provide superimposed taut lengths offilm positioned between said sealing pad and said heater and forming anenvelope open along one side and the ends of the workpiece, drivemechanism providing relative movement of said heater and said sealingpad between a receiving position and a sealing-severing position, a filmsupply drive for withdrawing film from a roll on said supply mechanismand feeding the film into the longitudinal reach of film, said filmsupply drive being controlled by said tensioning means in response tothe tension in the reach of film so as to maintain the reach of filmtaut during the operation of said drive mechanism between the receivingpositions and the sealingsevering positions of said heater and saidsealing pad, said sealing pad and said heater in said receiving positionbeing spaced apart to receive a workpiece in said work area, saidsealing pad and said heater in said sealing-severing position beingjuxtaposed to place said heater in contact with the superimposed lengthsof film to seal and sever the same along one side and the ends of theworkpiece, thus to provide a package of a workpiece in a closed envelopeof the heat-scalable film and to reestablish a longitudinal reach offilm adjacent to said sealing pad.

112. A machine for packaging a workpiece in a heat-scalable film, saidmachine comprising a frame, a generally Ushaped sealing pad mounted onsaid frame and defining within said sealing pad a work area, a firstfilm supply mechanism mounted on said frame for rotatably supporting afirst roll of heat-scalable film, a second film supply mechanism mountedon said frame for rotatably supporting a second roll of heatsealablefilm, said first and second film supply mechanisms being spaced apart toprovide a reach of film normally disposed adjacent to said sealing pad,the film from the first and second rolls of film being joined at a seamextending transversely of the reach of film adjacent to said sealingpad, a generally U-shaped heater mounted on said frame and shaped andarranged to overlie said sealing pad, means for urging a workpieceagainst the reach of film and into said work area to providesuperimposed lengths of film positioned between said sealing pad andsaid heater and forming an envelope open along one side and the ends ofthe workpiece, the film for forming the envelope being withdrawn fromthe rolls of film on said first and second supply mechanisms, drivemechanism providing relative movement of said heater and said sealingpad between a receiving position and a sealing-severing position, meansfor operating one of said supply mechanisms to withdraw film from theroll of film supported thereon to supply the same to the reach of filmfor forming the greater portion of the envelope during movement of saidheater and said sealing pad to said sealing-severing position, saidsealing pad and said heater in said receiving position being spacedapart to receive a workpiece in said work area, said sealing pad andsaid heater in said sealing-severing position being juxtaposed to placesaid heater in contact with the superimposed lengths of film to seal andsever the same along one side and the ends of the workpiece, thus toprovide a package of a workpiece in a closed envelope of theheat-scalable film and to reestablish a reach of film adjacent to saidsealing pad with a seam extending transversely of the reach of filmadjacent to said sealing pad.

13. The machine defined in claim 12, wherein said means for withdrawingfilm from one of said film supply mechanisms is operative to withdrawfilm from the roll on said first film supply mechanism and during themovement of said sealing pad and said heater to the sealing-severingpositions thereof.

It. The machine defined in claim 12, wherein said means for withdrawingfilm from one of said film supply mechanisms is operative to withdrawfilm from the roll on said second film supply mechanism after themovement of said sealing pad and said heater to the sealing-severingpositions thereof to change the position of the seam relative thereto.

35. A machine for packaging a workpiece in a heat-scalable film, saidmachine comprising a frame, a generally U-shaped sealing pad mounted onsaid frame and defining within said sealing pad a work area, a firstfilm supply mechanism mounted on said frame for rotatably supporting afirst roll of heat-scalable film, a second film supply mechanism mountedon said frame for rotatably supporting a second roll of heatsealablefilm, said first and second film supply mechanisms being spaced apart toprovide a longitudinal reach of film normally disposed adjacent to saidsealing pad, the film from the first and second rolls of film beingjoined at a seam extending transversely of the reach of film adjacent tosaid sealing pad, a generally U-shaped heater mounted on said frame andshaped and arranged to overlie said sealing pad, means for urging aworkpiece against the reach of film and into said work area to providesuperimposed lengths of film positioned between said sealing pad andsaid heater and forming an envelope open along one side and the ends ofthe workpiece, drive mechanism providing relative movement of saidheater and said sealing pad between a receiving position and asealingsevering position, means for operating said first supplymechanism to withdraw film from the first roll to supply the same to thereach of film during movement of said heater and said sealing pad tosaid sealing-severing position for forming the envelope, means foroperating said second supply mechanism to withdraw film from the secondroll to supply a small amount of the same to the reach of film when saidheater and said sealing pad are in said sealing-severing position forindexing the seam with respect to said sealing pad, said sealing pad andsaid heater in said receiving position being spaced apart to receive aworkpiece in said work area, said sealing pad and said heater in saidsealing-severing position being juxtaposed to place said heater incontact with the superimposed lengths of film to seal and sever the samealong one side and the ends of the workpiece, thus to provide a packageof a workpiece in a closed envelope of the heat-scalable film and toreestablish a longitudinal reach of film adjacent to said sealing padwith a seam extending transversely of the reach of film adjacent to saidsealing pad.

to. A machine for packaging a workpiece in a heat-sealable film, saidmachine comprising a frame, a generally U-shaped sealing pad mounted onsaid frame and defining within said sealing pad a work area, means forestabiishing a longitudinal reach of film normally disposed adjacent tosaid sealing pad, a generally U-shaped heater mounted on said frame andshaped and arranged to overlie said sealing pad, a feed platform mountedon said frame and shiftable between a workpiecereceiving position and aworkpiece-delivery position, said feed platform in saidworkpiece-delivery position being disposed adjacent to said sealing padin position to receive a workpiece, said feed platform in saidworkpiece-delivery position urging the workpiece against the reach offilmi and into said work area to provide superimposed lengths of filmpositioned between said sealing pad and said heater and forming anenvelope open along one side and the ends of the workpiece, and drivemechanism providing relative movement of said heater and said sealingpad between a receiving position and a sealing-severing position, saidsealing pad and said heater in said receiving position being spacedapart to receive a workpiece in said work area when said feed platform.is in said workpiecedelivery position, said sealing pad and said heaterin said sealing-severing position being juxtaposed to place said heaterin contact with the superimposed lengths of film to seal and sever thesame along one side and the ends of the workpiece, thus to provide apackage of a workpiece in a closed envelope of the heat-scalable filmand to reestablish a longitudinal reach of film adjacent to said sealingpad.

17. The machine set forth in claim in and further comprising seconddrive mechanism mounted on said frame for moving said platform betweensaid workpiece-receiving position and said workpiece-delivery position.

18. The machine defined in claim 16, and further comprising an infeedconveyor system adjacent said feed platform for transferring a workpieceto said feed platform when said feed platform is in saidworkpiece-receiving position.

19. A machine for packaging a workpiece in a heat-scalable film, saidmachine comprising a frame, a generally U-shaped sealing pad mounted onsaid frame and defining within said sealingpad a work area, a chutepositioned below said work area to receive a workpiece and extending toa discharge point, means for establishing a longitudinal reach of thefilm normally disposed adjacent to said sealing pad, a generally U-shaped heater mounted on said frame and shaped and arranged to overliesaid sealing pad, a feed platform mounted on said frame and shiftablebetween a workpiece-receiving position and a workpiece-deliveryposition, said feed platform in said workpiece-receiving position beingdisposed adjacent to said sealing pad in position to receive aworkpiece, said feed platform in said workpiece-delivery position urgingthe workpiece against the reach of film thereby causing the workpiece tofall into said work area and upon said chute to provide superimposedlengths of film positioned between said sealing pad and said heater andforming an envelope open along one side and the ends of the workpiece,and drive mechanism providing relative movement of said heater and saidsealing pao between a receiving position and a sealing-severingposition, said sealing pad and said heater in said receiving positionbeing spaced apart to receive a workpiece in said work area and uponsaid chute when said feed platform is in said workpiece-deliveryposition, said sealing pad and said heater in said sealing-severingposition being juxtaposed to place said heater in contact with thesuperimposed lengths of film to seal and to sever the same along oneside and the ends of the workpiece, thus to provide a package of aworkpiece in a closed envelope of the heat-scalable film and toreestablish a longitudinal reach of film adjacent to said sealing pad,the package exiting from said machine along said chute to said dischargepoint.

20. A machine for packaging a cylindrical workpiece in a heat-scalablefilm, said machine comprising a frame, a generally U-shaped sealing padfixedly mounted on said frame, said sealing pad having two spaced-apartgenerally parallel legs and a bight interconnecting said legs andextending therebeyond, said bight and said legs all having a centraltrough therealong and cooperating to define a work area therebetween,first cooling means disposed in said trough for cooling said sealingpad, a chute positioned below said work area to receive a workpiecethereon and extending to a discharge point, a first film supplymechanism mounted on said frame for rotatably supporting a first roll ofheat-scalable film, second film supply mechanism mounted on said framefor rotatably supporting a second roll of heat-scalable film, said firstand second supply mechanisms become spaced apart to provide alongitudinal reach of film normally disposed adjacent to said sealingpad and having a width no greater than the length of said bight with aseam extending transversely thereof, a generally U-shaped heatershiftably mounted on said frame and having two spaced-apart generallyparallel legs and a bight interconnecting said legs and extendingtherebeyond, a guide mounted on said heater and having second coolingmeans in thermal contact therewith, a feed platform mounted on saidframe and shiftable between a workpiece-receiving position and aworkpiece-delivery position, said feed platform in saidworkpiece-receiving position being disposed adjacent to said sealing padin position to receive a workpiece, said feed platform in saidworkpiecedelivery position urging the workpiece against the reach offilm and into said work area and onto said chute to provide superimposedlengths of film positioned between said sealing pad and said heater andforming an envelope open along one side and the ends of the workpiece,drive mechanism providing movement of said heater between a receivingposition and a sealing-severing position, tensioning means mounted onsaid frame for maintaining the reach of film taut, means for operatingsaid first supply mechanism to withdraw film from the first roll tosupply the same to the reach of film during movement of said heater andsaid sealing pad to said sealing-severing position for forming theenvelope, means for operating said second supply mechanism to withdrawfilm from the second roll to supply a small amount of the same to thereach of film when said heater and said sealing pad are in saidsealing-severing position for indexing the seam with respect to saidsealing pad, said heater in said receiving position being spaced apartfrom said sealing pad to receive a workpiece in said work area, saidheater in said sealing-severing position being juxtaposed with saidsealing pad to place said heater in contact with the superimposedlengths of the film to seal and sever the same along one side and theends of the workpiece, said first and second cooling means cooperatingwhen said heater is in said sealing-severing position to cool thelengths of film adjacent to said heater and said sealing pad, thus toprovide a package of a workpiece in a closed envelope of theheat-sealable film and to reestablish a longitudinal reach of filmadjacent to said sealing pad with a seam extending transversely of thereach of film adjacent to said sealing pad, the package exiting fromsaid machine along said chute to said discharge point.

21. A machine for packaging a workpiece in a heat-scalable film, saidmachine comprising a frame, a general U-shaped sealing pad mounted onsaid frame and defining within said sealing pad a work area, a supplymechanism mounted on said frame for rotatably supporting a roll ofheat-scalable film and to provide a longitudinal reach of film normallydisposed adjacent to said sealing pad, said supply mechanism including afirst idler roller mounted on said frame for rotation about a fixed axisand a second idler roller swingably mounted upon said frame for rotationabout a shiftable axis and a drive roller mounted on said frame forrotation about a fixed axis, said second idler roller being disposedbetween said first idler roller and said drive roller and cooperatingwith said first idler roller to support a roll of heat-sealable filmthereon, a generally U-shaped heater mounted on said frame and shapedand arranged to overlie said sealing pad, means for urging a workpieceagainst the reach of film and into said work area to providesuperimposed lengths of film positioned between said sealing pad andsaid heater and forming an envelope open along one side and the ends ofthe workpiece, drive mechanism providing relative movement of saidheater and said sealing pad between a receiving position and asealingsevering position, said sealing pad and said heater in saidreceiving position being spaced apart to receive a workpiece in saidwork area, said sealing pad and said heater in said sealing-severingposition being juxtaposed to place said heater in contact with thesuperimposed lengths of film to seal and sever the same along one sideand the ends of the workpiece, thus to provide a package of a workpiecein a closed envelope of the heat-scalable film and to reestablish alongitudinal reach of film adjacent to said sealing pad.

22. A machine for packaging a workpiece in a heat-scalable film, saidmachine comprising a frame, a generally U-shaped sealing pad mounted onsaid frame and defining within said sealing pad a work area, a firstfilm supply mechanism mounted on said frame for rotatably supporting afirst roll of heat-scalable film, a second film supply mechanism mountedon said frame for rotatably supporting a second roll of heatsealablefilm, each of said film supply mechanisms including a first idler rollermounted on said frame for rotation about a fixed axis and a second idlerroller swingably mounted upon said frame for rotation upon a shiftableaxis and a drive mechanism mounted upon said frame for rotation about afixed axis, said second idler roller being disposed between said firstidler roller and said drive roller in each of said supply mechanisms andcooperating with said first idler roller to support an associated rollof heat-scalable film thereon, said first and second film supplymechanisms being spaced apart to provide a longitudinal reach of filmnormally disposed adjacent to said sealing pad, the film from the firstand second rolls of film being joined at a seam extending transverselyof the reach of film adjacent to said sealing pad, a generally U-shapedheater mounted on said frame and shaped and arranged to overlie

1. A machine for packaging a workpiece in a heat-sealable film, saidmachine comprising a frame, a generally U-shaped sealing pad mounted onsaid frame and shaped to form a film bridge defining a central U-shapedtrough therein and defining within said sealing pad a work area, meansfor establishing a longitudinal reach of film normally disposed adjacentto said sealing pad, a generally U-shaped heater mounted on said frameand shaped and arranged to overlie said sealing pad, means for urging aworkpiece against the reach of film and into said work area to providesuperimposed lengths of film positioned between said sealing pad andsaid heater and forming an envelope open along one side and the ends ofthe workpiece, drive mechanism providing relative movement of saidheater and said sealing pad between a receiving position and asealing-severing position, said sealing pad and said heat in saidreceiving position being spaced apart to receive a workpiece in saidwork area, said sealing pad and said heater in said sealing-severingposition being juxtaposed to place said heater in said trough and incontact with the superimposed lengths of film to seal and sever the samealong one side and the ends of the workpiece, thus to provide a packageof a workpiece in a closed envelope of the heat-sealable film and toreestablish a longitudinal reach of film adjacent to said sealing pad.2. The machine defined in claim 1, wherein said sealing pad includes apair of spaced-apart generally U-shaped yieldable pads.
 3. The machinedefined in claim 2, wherein said yieldable pads are made of spongerubber.
 4. The machine defined in claim 1, wherein said sealing pad isfixedly mounted on said frame said heater is shiftably mounted on saidframe and movable between said sealing-severing position and saidreceiving position.
 5. The machine defined in claim 1, whereIn saidheater includes a generally U-shaped knife edge shaped to overlie thetrough in said sealing pad.
 6. A machine for packaging a workpiece in aheat-sealable film, said machine comprising a frame, a generallyU-shaped sealing pad mounted on said frame and defining within saidsealing pad a work area, a supply mechanism mounted on said frame forrotatably supporting a roll of heat-sealable film to provide a reach offilm normally disposed adjacent to said sealing pad, a generallyU-shaped heater mounted on said frame and shaped and arranged to overliesaid sealing pad, means for urging a workpiece against the reach of filmand into said work area to provide superimposed lengths of filmpositioned between said sealing pad and said heater and forming anenvelope open along one side and the ends of the workpiece, drivemechanism providing relative movement of said heater and said sealingpad between a receiving position and a sealing-severing position, meansfor operating said supply mechanism to withdraw film from the roll ofheat-sealable film to supply the same to the reach of film for formingthe envelope during movement of said heater and said sealing pad to saidsealing-severing position, said sealing pad and said heater in saidreceiving position being spaced apart to receive a workpiece in saidwork area, said sealing pad and said heater in said sealing-severingposition being juxtaposed to place said heater in contact with thesuperimposed lengths of film to seal and sever the same on one side andthe ends of the workpiece, thus to provide a package of a workpiece in aclosed envelope of a heat-sealable film and to reestablish a reach offilm adjacent to said sealing pad.
 7. The machine set forth in claim 6,wherein said supply mechanism includes a pair of horizontally disposedspaced-apart rolls for holding a roll of heat-sealable film thereon. 8.The machine set forth in claim 6, wherein said supply mechanism ismounted above said sealing pad and said heater to feed the longitudinalreach of film downwardly adjacent to said sealing pad.
 9. The machineset forth in claim 6, and further comprising drive structure positivelyto feed film from a roll thereof mounted on said supply mechanism.
 10. Amachine for packaging a workpiece in a heat-sealable film, said machinecomprising a frame, a generally U-shaped sealing pad mounted on saidframe and defining within said sealing pad a work area, a supplymechanism mounted on said frame for rotatably supporting a roll ofheat-sealable film to provide a longitudinal reach of film normallydisposed adjacent to said sealing pad, a generally U-shaped heatermounted on said frame and shaped and arranged to overlie said sealingpad, means for urging a workpiece against the reach of film and intosaid work area to provide superimposed lengths of film positionedbetween said pad and said heater and forming an envelope open along oneside and the ends of the workpiece, drive mechanism providing relativemovement of said heater and said sealing pad between a receivingposition and a sealing-severing position, means for anchoring the filmon the side of said work area opposite that on which is disposed saidsupply mechanism, operation of said drive mechanism to move said heaterand said sealing pad toward one another causing film to be fed from aroll thereof mounted on said supply mechanism into the longitudinalreach of film, said sealing pad and said heater in said receivingposition being spaced apart to receive a workpiece in said work area,said sealing pad and said heater in said sealing-severing position beingjuxtaposed to place said heater in contact with the superimposed lengthsof film to seal and sever the same along one side and the ends of theworkpiece, thus to provide a package of a workpiece in a closed envelopeof the heat-sealable film and to reestablish a longitudinal reach offilm adjacent to said sealing pad.
 11. A machine for packaging aworkpiece in a heat-sealable fIlm, said machine comprising a frame, agenerally U-shaped sealing pad mounted on said frame and defining withinsaid sealing pad a work area, a supply mechanism mounted on said framefor rotatably supporting a roll of heat-sealable film to provide alongitudinal reach of film normally disposed adjacent to said sealingpad, a generally U-shaped heater mounted on said frame and shaped andarranged to overlie said sealing pad, tensioning mechanism mounted onsaid frame for maintaining the reach of film taut, means for urging aworkpiece against the taut reach of film and into said work area toprovide superimposed taut lengths of film positioned between saidsealing pad and said heater and forming an envelope open along one sideand the ends of the workpiece, drive mechanism providing relativemovement of said heater and said sealing pad between a receivingposition and a sealing-severing position, a film supply drive forwithdrawing film from a roll on said supply mechanism and feeding thefilm into the longitudinal reach of film, said film supply drive beingcontrolled by said tensioning means in response to the tension in thereach of film so as to maintain the reach of film taut during theoperation of said drive mechanism between the receiving positions andthe sealing-severing positions of said heater and said sealing pad, saidsealing pad and said heater in said receiving position being spacedapart to receive a workpiece in said work area, said sealing pad andsaid heater in said sealing-severing position being juxtaposed to placesaid heater in contact with the superimposed lengths of film to seal andsever the same along one side and the ends of the workpiece, thus toprovide a package of a workpiece in a closed envelope of theheat-sealable film and to reestablish a longitudinal reach of filmadjacent to said sealing pad.
 12. A machine for packaging a workpiece ina heat-sealable film, said machine comprising a frame, a generallyU-shaped sealing pad mounted on said frame and defining within saidsealing pad a work area, a first film supply mechanism mounted on saidframe for rotatably supporting a first roll of heat-sealable film, asecond film supply mechanism mounted on said frame for rotatablysupporting a second roll of heat-sealable film, said first and secondfilm supply mechanisms being spaced apart to provide a reach of filmnormally disposed adjacent to said sealing pad, the film from the firstand second rolls of film being joined at a seam extending transverselyof the reach of film adjacent to said sealing pad, a generally U-shapedheater mounted on said frame and shaped and arranged to overlie saidsealing pad, means for urging a workpiece against the reach of film andinto said work area to provide superimposed lengths of film positionedbetween said sealing pad and said heater and forming an envelope openalong one side and the ends of the workpiece, the film for forming theenvelope being withdrawn from the rolls of film on said first and secondsupply mechanisms, drive mechanism providing relative movement of saidheater and said sealing pad between a receiving position and asealing-severing position, means for operating one of said supplymechanisms to withdraw film from the roll of film supported thereon tosupply the same to the reach of film for forming the greater portion ofthe envelope during movement of said heater and said sealing pad to saidsealing-severing position, said sealing pad and said heater in saidreceiving position being spaced apart to receive a workpiece in saidwork area, said sealing pad and said heater in said sealing-severingposition being juxtaposed to place said heater in contact with thesuperimposed lengths of film to seal and sever the same along one sideand the ends of the workpiece, thus to provide a package of a workpiecein a closed envelope of the heat-sealable film and to reestablish areach of film adjacent to said sealing pad with a seam extendingtransversely of the reach of film adjacent to sAid sealing pad.
 13. Themachine defined in claim 12, wherein said means for withdrawing filmfrom one of said film supply mechanisms is operative to withdraw filmfrom the roll on said first film supply mechanism and during themovement of said sealing pad and said heater to the sealing-severingpositions thereof.
 14. The machine defined in claim 12, wherein saidmeans for withdrawing film from one of said film supply mechanisms isoperative to withdraw film from the roll on said second film supplymechanism after the movement of said sealing pad and said heater to thesealing-severing positions thereof to change the position of the seamrelative thereto.
 15. A machine for packaging a workpiece in aheat-sealable film, said machine comprising a frame, a generallyU-shaped sealing pad mounted on said frame and defining within saidsealing pad a work area, a first film supply mechanism mounted on saidframe for rotatably supporting a first roll of heat-sealable film, asecond film supply mechanism mounted on said frame for rotatablysupporting a second roll of heat-sealable film, said first and secondfilm supply mechanisms being spaced apart to provide a longitudinalreach of film normally disposed adjacent to said sealing pad, the filmfrom the first and second rolls of film being joined at a seam extendingtransversely of the reach of film adjacent to said sealing pad, agenerally U-shaped heater mounted on said frame and shaped and arrangedto overlie said sealing pad, means for urging a workpiece against thereach of film and into said work area to provide superimposed lengths offilm positioned between said sealing pad and said heater and forming anenvelope open along one side and the ends of the workpiece, drivemechanism providing relative movement of said heater and said sealingpad between a receiving position and a sealing-severing position, meansfor operating said first supply mechanism to withdraw film from thefirst roll to supply the same to the reach of film during movement ofsaid heater and said sealing pad to said sealing-severing position forforming the envelope, means for operating said second supply mechanismto withdraw film from the second roll to supply a small amount of thesame to the reach of film when said heater and said sealing pad are insaid sealing-severing position for indexing the seam with respect tosaid sealing pad, said sealing pad and said heater in said receivingposition being spaced apart to receive a workpiece in said work area,said sealing pad and said heater in said sealing-severing position beingjuxtaposed to place said heater in contact with the superimposed lengthsof film to seal and sever the same along one side and the ends of theworkpiece, thus to provide a package of a workpiece in a closed envelopeof the heat-sealable film and to reestablish a longitudinal reach offilm adjacent to said sealing pad with a seam extending transversely ofthe reach of film adjacent to said sealing pad.
 16. A machine forpackaging a workpiece in a heat-sealable film, said machine comprising aframe, a generally U-shaped sealing pad mounted on said frame anddefining within said sealing pad a work area, means for establishing alongitudinal reach of film normally disposed adjacent to said sealingpad, a generally U-shaped heater mounted on said frame and shaped andarranged to overlie said sealing pad, a feed platform mounted on saidframe and shiftable between a workpiece-receiving position and aworkpiece-delivery position, said feed platform in saidworkpiece-delivery position being disposed adjacent to said sealing padin position to receive a workpiece, said feed platform in saidworkpiece-delivery position urging the workpiece against the reach offilm and into said work area to provide superimposed lengths of filmpositioned between said sealing pad and said heater and forming anenvelope open along one side and the ends of the workpiece, and drivemechanism providing relative movement of said heater aNd said sealingpad between a receiving position and a sealing-severing position, saidsealing pad and said heater in said receiving position being spacedapart to receive a workpiece in said work area when said feed platformis in said workpiece-delivery position, said sealing pad and said heaterin said sealing-severing position being juxtaposed to place said heaterin contact with the superimposed lengths of film to seal and sever thesame along one side and the ends of the workpiece, thus to provide apackage of a workpiece in a closed envelope of the heat-sealable filmand to reestablish a longitudinal reach of film adjacent to said sealingpad.
 17. The machine set forth in claim 16 and further comprising seconddrive mechanism mounted on said frame for moving said platform betweensaid workpiece-receiving position and said workpiece-delivery position.18. The machine defined in claim 16, and further comprising an infeedconveyor system adjacent said feed platform for transferring a workpieceto said feed platform when said feed platform is in saidworkpiece-receiving position.
 19. A machine for packaging a workpiece ina heat-sealable film, said machine comprising a frame, a generallyU-shaped sealing pad mounted on said frame and defining within saidsealing pad a work area, a chute positioned below said work area toreceive a workpiece and extending to a discharge point, means forestablishing a longitudinal reach of the film normally disposed adjacentto said sealing pad, a generally U-shaped heater mounted on said frameand shaped and arranged to overlie said sealing pad, a feed platformmounted on said frame and shiftable between a workpiece-receivingposition and a workpiece-delivery position, said feed platform in saidworkpiece-receiving position being disposed adjacent to said sealing padin position to receive a workpiece, said feed platform in saidworkpiece-delivery position urging the workpiece against the reach offilm thereby causing the workpiece to fall into said work area and uponsaid chute to provide superimposed lengths of film positioned betweensaid sealing pad and said heater and forming an envelope open along oneside and the ends of the workpiece, and drive mechanism providingrelative movement of said heater and said sealing pad between areceiving position and a sealing-severing position, said sealing pad andsaid heater in said receiving position being spaced apart to receive aworkpiece in said work area and upon said chute when said feed platformis in said workpiece-delivery position, said sealing pad and said heaterin said sealing-severing position being juxtaposed to place said heaterin contact with the superimposed lengths of film to seal and to severthe same along one side and the ends of the workpiece, thus to provide apackage of a workpiece in a closed envelope of the heat-sealable filmand to reestablish a longitudinal reach of film adjacent to said sealingpad, the package exiting from said machine along said chute to saiddischarge point.
 20. A machine for packaging a cylindrical workpiece ina heat-sealable film, said machine comprising a frame, a generallyU-shaped sealing pad fixedly mounted on said frame, said sealing padhaving two spaced-apart generally parallel legs and a bightinterconnecting said legs and extending therebeyond, said bight and saidlegs all having a central trough therealong and cooperating to define awork area therebetween, first cooling means disposed in said trough forcooling said sealing pad, a chute positioned below said work area toreceive a workpiece thereon and extending to a discharge point, a firstfilm supply mechanism mounted on said frame for rotatably supporting afirst roll of heat-sealable film, second film supply mechanism mountedon said frame for rotatably supporting a second roll of heat-sealablefilm, said first and second supply mechanisms become spaced apart toprovide a longitudinal reach of film normally disposed adjacent to saidsealing pad and having a Width no greater than the length of said bightwith a seam extending transversely thereof, a generally U-shaped heatershiftably mounted on said frame and having two spaced-apart generallyparallel legs and a bight interconnecting said legs and extendingtherebeyond, a guide mounted on said heater and having second coolingmeans in thermal contact therewith, a feed platform mounted on saidframe and shiftable between a workpiece-receiving position and aworkpiece-delivery position, said feed platform in saidworkpiece-receiving position being disposed adjacent to said sealing padin position to receive a workpiece, said feed platform in saidworkpiece-delivery position urging the workpiece against the reach offilm and into said work area and onto said chute to provide superimposedlengths of film positioned between said sealing pad and said heater andforming an envelope open along one side and the ends of the workpiece,drive mechanism providing movement of said heater between a receivingposition and a sealing-severing position, tensioning means mounted onsaid frame for maintaining the reach of film taut, means for operatingsaid first supply mechanism to withdraw film from the first roll tosupply the same to the reach of film during movement of said heater andsaid sealing pad to said sealing-severing position for forming theenvelope, means for operating said second supply mechanism to withdrawfilm from the second roll to supply a small amount of the same to thereach of film when said heater and said sealing pad are in saidsealing-severing position for indexing the seam with respect to saidsealing pad, said heater in said receiving position being spaced apartfrom said sealing pad to receive a workpiece in said work area, saidheater in said sealing-severing position being juxtaposed with saidsealing pad to place said heater in contact with the superimposedlengths of the film to seal and sever the same along one side and theends of the workpiece, said first and second cooling means cooperatingwhen said heater is in said sealing-severing position to cool thelengths of film adjacent to said heater and said sealing pad, thus toprovide a package of a workpiece in a closed envelope of theheat-sealable film and to reestablish a longitudinal reach of filmadjacent to said sealing pad with a seam extending transversely of thereach of film adjacent to said sealing pad, the package exiting fromsaid machine along said chute to said discharge point.
 21. A machine forpackaging a workpiece in a heat-sealable film, said machine comprising aframe, a general U-shaped sealing pad mounted on said frame and definingwithin said sealing pad a work area, a supply mechanism mounted on saidframe for rotatably supporting a roll of heat-sealable film and toprovide a longitudinal reach of film normally disposed adjacent to saidsealing pad, said supply mechanism including a first idler rollermounted on said frame for rotation about a fixed axis and a second idlerroller swingably mounted upon said frame for rotation about a shiftableaxis and a drive roller mounted on said frame for rotation about a fixedaxis, said second idler roller being disposed between said first idlerroller and said drive roller and cooperating with said first idlerroller to support a roll of heat-sealable film thereon, a generallyU-shaped heater mounted on said frame and shaped and arranged to overliesaid sealing pad, means for urging a workpiece against the reach of filmand into said work area to provide superimposed lengths of filmpositioned between said sealing pad and said heater and forming anenvelope open along one side and the ends of the workpiece, drivemechanism providing relative movement of said heater and said sealingpad between a receiving position and a sealing-severing position, saidsealing pad and said heater in said receiving position being spacedapart to receive a workpiece in said work area, said sealing pad andsaid heater in said sealing-severing position being juxtapoSed to placesaid heater in contact with the superimposed lengths of film to seal andsever the same along one side and the ends of the workpiece, thus toprovide a package of a workpiece in a closed envelope of theheat-sealable film and to reestablish a longitudinal reach of filmadjacent to said sealing pad.
 22. A machine for packaging a workpiece ina heat-sealable film, said machine comprising a frame, a generallyU-shaped sealing pad mounted on said frame and defining within saidsealing pad a work area, a first film supply mechanism mounted on saidframe for rotatably supporting a first roll of heat-sealable film, asecond film supply mechanism mounted on said frame for rotatablysupporting a second roll of heat-sealable film, each of said film supplymechanisms including a first idler roller mounted on said frame forrotation about a fixed axis and a second idler roller swingably mountedupon said frame for rotation upon a shiftable axis and a drive mechanismmounted upon said frame for rotation about a fixed axis, said secondidler roller being disposed between said first idler roller and saiddrive roller in each of said supply mechanisms and cooperating with saidfirst idler roller to support an associated roll of heat-sealable filmthereon, said first and second film supply mechanisms being spaced apartto provide a longitudinal reach of film normally disposed adjacent tosaid sealing pad, the film from the first and second rolls of film beingjoined at a seam extending transversely of the reach of film adjacent tosaid sealing pad, a generally U-shaped heater mounted on said frame andshaped and arranged to overlie said sealing pad, means for urging aworkpiece against the reach of film and into said work area to providesuperimposed lengths of film positioned between said sealing pad andsaid heater and forming an envelope open along one side and the ends ofthe workpiece, the film for forming the envelope being withdrawn fromthe rolls of film on said first and second supply mechanisms, drivemechanism providing relative movement of said heater and said sealingpad between a receiving position and a sealing-severing position, saidsealing pad and said heater in said receiving position being spacedapart to receive a workpiece in said work area, said sealing pad andsaid heater in said sealing-severing position being juxtaposed to placesaid heater in contact with the superimposed lengths of film to seal andsever the same along one side and the ends of the workpiece, thus toprovide a package of a workpiece in a closed envelope of theheat-sealable film and to reestablish a longitudinal reach of filmadjacent to said sealing pad with a seam extending transversely of thereach of film adjacent to said sealing pad.
 23. A machine for packaginga workpiece in a heat-sealable film, said machine comprising a frame, agenerally U-shaped sealing pad mounted on said frame and having aU-shaped central trough therein and defining within said sealing pad awork area, means for establishing a reach of film normally disposedadjacent to said sealing pad, a generally U-shaped heater mounted onsaid frame and shaped and arranged to overlie said sealing pad, a filmguide mounted on said frame adjacent to said heater and positionednormally to hold the film adjacent to but out of contact with saidheater, means for urging a workpiece against the reach of film and intosaid work area, drive mechanism providing relative movement of saidheater with said guide and said sealing pad between a receiving positionand a sealing-severing position, said guide and said sealing padcooperating in the sealing-severing positions thereof to providesuperimposed lengths of film positioned therebetween and forming anenvelope open along one side and the ends of the workpiece, said heaterin the sealing-severing position thereof overlying trough and contactingthe superimposed lengths of film bridged thereacross to seal and severthe same along one side and the ends of thE workpiece, said sealing padhaving the surfaces thereof adjacent to said trough sloping away fromsaid trough and said guide, said guide including spaced-apart portionsbridging said trough in the sealing-severing positions of the parts tohold the superimposed lengths of film taut across said trough, thus toprovide a package of a workpiece in a closed envelope of theheat-sealable film and to reestablish a reach of film adjacent to saidsealing pad.
 24. A machine for packaging a workpiece in a heat-sealablefilm, said machine comprising a frame, a generally U-shaped sealing padmounted on said frame and defining within said sealing pad a work area,a first film supply mechanism mounted on said frame for rotatablysupporting a first roll of heat-sealable film, a second film supplymechanism mounted on said frame for rotatably supporting a second rollof heat-sealable film, said first and second film supply mechanismsbeing spaced apart to provide a reach of film normally disposed adjacentto said sealing pad, the film from the first and second rolls of filmbeing joined at a seam extending transversely of the reach of filmadjacent to said sealing pad, tensioning means mounted on said frameadjacent to one of said film supply mechanisms for maintaining the reachof film taut, a generally U-shaped heater mounted on said frame andshaped and arranged to overlie said sealing pad, means for urging aworkpiece against the reach of film and into said work area to providesuperimposed lengths of film positioned between said sealing pad andsaid heater and forming an envelope open along one side and the ends ofthe workpiece, the film for forming the envelope being withdrawn fromthe rolls of film on said first and second supply mechanisms, drivemechanism providing relative movement of said heater and said sealingpad between a receiving position and a sealing-severing position, saidsealing pad and said heater in said receiving position being spacedapart to receive a workpiece in said work area, said sealing pad andsaid heater in said sealing-severing position being juxtaposed to placesaid heater in contact with the superimposed lengths of film to seal andsever the same along one side and the ends of the workpiece, thus toprovide a package of a workpiece in a closed envelope of theheat-sealable film and to reestablish a reach of film adjacent to saidsealing pad with a seam extending transversely of the reach of filmadjacent to said sealing pad.
 25. A machine for packaging a workpiece ina heat-sealable film, said machine comprising a frame, a generallyU-shaped sealing pad mounted on said frame and defining within saidsealing pad a work area, means for establishing a reach of film normallydisposed adjacent to said sealing pad, a generally U-shaped heatermounted on said frame and shaped and arranged to overlie said sealingpad, a feed platform pivotally mounted on said frame and pivotablebetween a workpiece-receiving position and a workpiece-deliveryposition, said feed platform in said workpiece-receiving position beingdisposed adjacent to said sealing pad in position to receive aworkpiece, said feed platform in said workpiece-delivery position urgingthe workpiece against the reach of film and into said work area toprovide superimposed lengths of film positioned between said sealing padand said heater and forming an envelope open along one side and the endsof the workpiece, and drive mechanism providing relative movement ofsaid heater and said sealing pad between a receiving position and asealing-severing position, said sealing pad and said heater in saidreceiving position being spaced apart to receive a workpiece in saidwork area when said feed platform is in said workpiece-deliveryposition, said sealing pad and said heater in said sealing-severingposition being juxtaposed to place said heater in contact with thesuperimposed lengths of film to seal and sever the same along one sideand the ends of the workpiece, thus to provide a package of a woRkpiecein a closed envelope of the heat-sealable film and to reestablish areach of film adjacent to said sealing pad.
 26. A method of packaging acylindrical workpiece in a heat-sealable film comprising establishing alongitudinal reach of film including lengths from two spaced-apart filmsupplies joined together at a seam extending transversely of the reachof film, urging the workpiece along an entire longitudinal side thereofagainst a reach of film to form an envelope open along a longitudinalside and at least one end of the workpiece, withdrawing film from one ofthe film supplies to form the envelope during the urging of theworkpiece against the reach of film, heat-sealing the open portions ofthe envelope to form a package of a cylindrical workpiece in a closedenvelope and indexing the other film supply during the heat-sealing ofthe envelope to introduce a small amount of film into the reach of filmand provide displacement of the seam.